Such supports are described, in particular, in French patents numbers 81 06 882 and 86 16 064, and in U.S. Pat. Nos. 3,893,449 and 4,483,344.
These supports serve to hold a transducer against a point on the body of a patient while enabling the angular position of the transducer axis to be adjusted to a certain extent relative to the surface with which the transducer is in contact.
The purpose of such angular positioning is to point the transducer towards the organ under examination, since it is not always possible to place the transducer immediately thereover.
Thus, when performing echocardiography, the practitioner begins by finding an intercostal window on the chest of the patient, after which the transducer is applied and pressed against said location, and finally the transducer is pointed so as to aim at the region of the heart to be examined by looking for the best viewing angle.
The above-mentioned patents describe a transducer support comprising:
a base having a contact surface suitable for being pressed against the body of a patient at the position which is to be examined;
a transducer carrier removeably receiving the transducer and provided with means for urging the transducer axially against the body of the patient;
means for mounting the transducer carrier on the base with the possibility of pointing the transducer carrier by pivoting; and
locking means for locking the transducer carrier in position.
In practice, it is desirable for the transducer carrier to pivot about a point situated in the immediate proximity of the contact surface, as described in French patent 8106882 and the equivalent U.S. Pat. No. 4,483,344.
However, the support described in these two patents provide only a small degree of angular freedom for the transducer carrier about the normal to the plane of contact, and this can give rise to difficulties in some situations. This drawback is compensated to some extent by the fact that the transducer carrier is mounted on equipment which is moveable in translation along two perpendicular directions in order to change the point of contact without changing the position of the base, while the base is fixed to the patient's body by straps, however this gives rise to a transducer support whose mechanical structure is complex and the transducer cannot be changed quickly because that requires various parts of the transducer carrier to be disassembled.
One of the aims of the present invention is to provide a transducer support of the above-specified type which mitigates these drawbacks by providing for a very large degree of angular displacement relative to the normal to the contact plane, with rotation being performed about a fixed point which is as close as possible to the body of the patient.